Objective: To continue investigation of possible causes of Sudden Infant Death Syndrome by intensive monitoring of physiologic data for evidence of acute episodes of disordered cardiorespiratory or thermoregulatory function. Accomplished: Special purpose wireless monitoring devices were designed and developed and used to acquire approximately two months usable data from six infants in a hospital setting. A data compression system for rapid examination of data, with convenient retrieval and "real-time" readout was assembled and utilized. Feasibility of long term monitoring of heart rate, respiratory rate and skin temperature in small infants with our non-encumbering telemetry transmitter has been well demonstrated. Goals during renewal period: Acquire ten additional patient months of physiologic data; begin monitoring in the hospital and continue in the home. Analyze data and prepare manuscript for publication.